Richard of Conisburgh, 3rd Earl of Cambridge

Richard of Conisburgh, 3rd Earl of Cambridge (20 July 1375-5 August 1415) was an English nobleman who was beheaded for his part in the Southampton Plot, a conspiracy against King Henry V of England.

Biography
Richard of Conisburgh was born in Conisburgh Castle, Yorkshire, England in 1375, the son of Edmund of Langley, 1st Duke of York and Isabella of Castile. On his father's side, he was the grandson of King Edward III of England and Philippa of Hainault, while he was the maternal grandson of King Peter of Castile. His father did not recognize him as a full blood relative, but his mother persuaded King Richard II of England to give Conisburgh an annuity from Yorkshire. Richard received no favors from Henry IV of England after Richard II's overthrow, and his annuities were either paid irregularly, or not paid at all. From 1403 to 1404, he defended Herefordshire against Owain Glyndwr's Welsh rebels, and he befriended the Mortimer and Cherleton families. In 1406, he was knighted in order to escort Philippa of England to marry Eric of Pomerania.

In 1414, Richard was created Earl of Cambridge, succeeding his older brother, Edward of Norwich, 2nd Earl of Cambridge, who resigned the title. However, this title was not accompanied by any lands, and he lacked the equipment to prepare himself for campaigning in France under King Henry V of England. Partly for this reason, he took part in the Southampton Plot against King Henry, but Edmund Mortimer, 5th Earl of March revealed this plan to the King. On 5 August 1415, Cambridge was beheaded for treason.